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The inflammatory myopathies (IM) are a group of heterogeneous disorders and include dermatomyositis (DM), polymyositis (PM), necrotising autoimmune myositis (NAM), and inclusion-body myositis (IBM). The main characteristic of these clinical entities is muscle weakness. DM and PM are characterised by the subacute onset of symmetric proximal muscle weakness and involvement of other organ systems such as lungs and skin, have a good response to immunosuppression and a strong association with autoantibodies. On the other hand, patients suffering from IBM, have symptoms from proximal but also distal muscles and typically the weakness is slowly progressive. IBM is not responding to immunosuppression as good as DM and PM. Other subtypes are dermatomyositis sine myositis (DSM) and overlap myositis (OM), a subtype which is beginning to be recognised in the literature. IM can occur as isolated inflammatory muscle disorders or associated with autoimmune rheumatic diseases like scleroderma (SCL), systemic lupus erythematosus (SLE), Sjögren’s syndrome (SS) or neoplasias.